Mix the minced meat with egg, salt, nutmeg. Form meatballs the size of a walnut and fry in hot olive oil. Clean the mushrooms, wash and cut into slices. Stew in 3 tbsp olive oil and 2-3 water for about five minutes. Add salt, then salt and pepper. In plenty of water boil the pasta not fully (as they say al dente). Drain and add the bechamel and the butter, mix. Add mushrooms and meatballs. Put everything in the appropriate tray and sprinkle with some breadcrumbs and a few tablespoons of butter. Bake at 200 C for about 20 minutes.